1. Technical Field
Various embodiments relate generally to an electronic device and, more particularly, to a three-dimensional semiconductor device and a manufacturing method thereof.
2. Related Art
A non-volatile memory device retains data even when a power supply is interrupted or blocked. Recently, as the integration enhancement of a two-dimensional memory device configured to manufacture a memory cell in a single layer on a silicon substrate has reached the limit, a non-volatile memory device having a three-dimensional structure where memory cells are stacked vertically over a silicon substrate has been proposed.
A three-dimensional non-volatile memory device includes interlayer insulating layers and word lines alternately stacked, and channel layers passing through the interlayer insulating layers and the word lines. Memory cells are stacked along the channel layers. Also, when manufacturing the three-dimensional non-volatile memory device, a plurality of oxide layers and a plurality of nitride layers are alternately stacked and the plurality of nitride layers are replaced with a plurality of conductive layers to form stacked word lines.
However, there is difficulty with the process of replacing the plurality of nitride layers with the plurality of conductive layers. In particular, the layers around the nitride layers may be damaged in the process of replacing the nitride layers with the conductive layers. As a result, the characteristics of the memory device may deteriorate.